package com.cloud.code.牛客网;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Scanner;

public class Test27 {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        while (scanner.hasNext()) {
            String a = scanner.nextLine();
            String b = scanner.nextLine();
            int count = scanner.nextInt();

            int[] aint = extracted(a);
            int[] bint = extracted(b);

            List<Integer> list = new ArrayList<>();
            for (int i = 0; i < aint.length; i++) {
                for (int j = 0; j < bint.length; j++) {
                    list.add(aint[i] + bint[j]);
                }
            }
            Collections.sort(list);

            int sum = 0;
            for (int i = 0; i < count; i++) {
                sum += list.get(i);
            }
            System.out.println(sum);
        }
    }

    private static int[] extracted(String a) {
        String[] astr = a.split(" ");
        int[] aint = new int[Integer.parseInt(astr[0])];
        for (int i = 0; i < aint.length; i++) {
            aint[i] = Integer.parseInt(astr[i + 1]);
        }

        return aint;
    }
}
